WO2007017969A1

WO2007017969A1 - Air conditioner and method of producing air conditioner

Info

Publication number: WO2007017969A1
Application number: PCT/JP2006/304434
Authority: WO
Inventors: Akira Ishibashi; Kunihiko Kaga; Riichi Kondou; Takuya Mukouyama
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2005-08-08
Filing date: 2006-03-08
Publication date: 2007-02-15
Also published as: EP1798490A1; JP4506609B2; JP2007046804A; CN101031754B; ES2425753T3; US20080282725A1; EP1798490B1; CN101031754A; EP1798490A4; US7703504B2

Abstract

An air conditioner in which heat transmission performance of a heat exchanger is improved and that has high energy efficiency. A heat exchanger (15) has fins (1) arranged side by side at predetermined intervals in the direction of a rotation shaft of a blower (5), heat transfer tubes (2) inserted substantially vertical to the fins (1), forming rows of the tubes in the longitudinal direction of the fins (1), and connected in the direction of airflow to form refrigerant flow paths, and branch sections provided at connection sections between the heat transfer tubes (2) and partly increasing or decreasing the number of paths of the refrigerant flow paths. The heat exchanger is constructed such that refrigerant flowing in each of the refrigerant flow channels, which pass different paths in at least a part between a refrigerant inlet and a refrigerant outlet, sequentially flows in one direction in the rows from a windward row to a leeward row or from the leeward row to the windward row in the airflow direction. Also, one path section is provided at a heat transmission tube on the most windward side. In addition, a fin (1) in intimate contact with a refrigerant outlet (18) and connection piping (16c) when the heat exchanger (15) is operated as a condenser is thermally separated by a separation means (21).

Description

Specification

Air conditioner and method of manufacturing air conditioner

Technical field

TECHNICAL FIELD [0001] The present invention relates to an air conditioner using a finned tube heat exchanger that performs heat exchange between a refrigerant and a fluid such as air, and a method for manufacturing the air conditioner.

Background art

[0002] Conventional indoor units of air conditioners include a refrigerant flow path of a heat exchanger configured by two paths, and the refrigerant is circulated so that the heat exchange amount is balanced in consideration of the wind speed. (For example, Patent Literature 1). In addition, there has been a configuration in which a heat exchange refrigerant flow path is configured by two passes and an expansion valve is provided in the middle of the refrigerant flow path to enable dry operation (see, for example, Patent Document 2). In addition, there has been a configuration in which the refrigerant flow path for heat exchange is configured with two passes and the amount of refrigerant flowing through each pass is balanced (see, for example, Patent Document 3). In addition, there has been a technology that suppresses an increase in pressure loss by increasing the refrigerant flow path of the heat exchanger to two passes and increasing the refrigerant flow passage area during the refrigerant evaporation process (for example, patents). (Ref. 4).

[0003] Patent Document 1: Japanese Patent Laid-Open No. 8-159502 (pages 2 to 3, FIG. 2)

Patent Document 2: Japanese Patent Application Laid-Open No. 2001-82759 (Pages 3-4, Figure 2)

Patent Document 3: Japanese Patent Application Laid-Open No. 7-27359 (page 2 to page 3, Fig. 2)

Patent Document 4: Japanese Patent Application Laid-Open No. 7-71841 (Pages 2 to 3, Figure 1)

Disclosure of the invention

Problems to be solved by the invention

[0004] In a conventional air conditioner having two refrigerant flow paths, the overall refrigerant flow rate is smaller than that of one path, and the heat transfer coefficient in the heat transfer tube is particularly low in the part where the refrigerant is supercooled. However, there was a problem that the heat exchange ability could not be increased. In addition, the configuration in which the 2-pass force is also branched into 4 passes is a part of the 1S refrigerant flow path that flows to different heat transfer pipe rows in the 1S refrigerant flow path between the refrigerant inlet and the refrigerant outlet. The leeward heat transfer tube and the leeward heat transfer tube to the windward heat transfer tube have a configuration with a portion that is directed in the opposite direction in one refrigerant flow path. Therefore, if you look at the temperature change in the entire flow, There was a problem that there was a part where the air temperature change and refrigerant temperature change were reversed, and the heat exchanger capacity could not be increased.

[0005] The present invention has been made to solve the above-described problems, and an object thereof is to improve the heat exchange performance of the heat exchanger and obtain an air conditioner with high energy efficiency. . Means for solving the problems aimed at obtaining a method of manufacturing an air conditioner that can be assembled relatively easily

[0006] The present invention includes a blower that guides a gas flowing from a suction port to a blower outlet, a heat exchanger that is provided on the suction port side of the blower and exchanges heat between the gas and a refrigerant, and the heat exchanger The cooling medium inlet and the refrigerant are inserted into the plurality of fins arranged in parallel at a predetermined interval in the rotation axis direction of the blower at a substantially right angle, arranged in a row in the longitudinal direction of the fins and connected in a plurality of rows in the airflow direction. A heat transfer pipe constituting a refrigerant flow path between the outlets, and a branch pipe connected to a connection portion of the heat transfer pipe and partially increasing or decreasing the number of paths of the refrigerant flow path by the heat transfer pipe, And the refrigerant flowing through each of the plurality of refrigerant flow paths passing through different paths at least partially between the refrigerant outlet and the leeward row or the leeward row force in the airflow direction. Specially configured to flow in sequence between columns. Is the Chi to.

The invention's effect

[0007] In the air conditioner of the present invention, the path is branched to form a refrigerant flow path, and flows through each of the plurality of refrigerant flow paths formed through different paths between the refrigerant inlet and the refrigerant outlet. Refrigerant force Upwind row force in the airflow direction Downstream row or leeward row force Since it is configured to flow in sequence in one direction in the upwind row, the air temperature change from the inlet to the outlet and the refrigerant inlet The refrigerant temperature change up to the outlet can be made almost in parallel, and heat transfer performance is improved by exchanging heat efficiently in any part of the heat exchange, resulting in an air conditioner with high energy efficiency.

Brief Description of Drawings

FIG. 1 is an explanatory diagram showing an internal configuration of a heat exchanger according to Embodiment 1 of the present invention.

FIG. 2 is a refrigerant circuit illustrating an example of a refrigerant circuit of an air conditioner according to Embodiment 1 of the present invention. FIG.

FIG. 3 is a side configuration diagram showing the indoor unit of the air conditioner according to Embodiment 1 of the present invention.

FIG. 4 is a front view showing a hairpin according to Embodiment 1 of the present invention.

[5] Front view, right side view, and bottom view showing a branch pipe according to Embodiment 1 of the present invention. [6] Heat exchange according to Embodiment 1 of the present invention was used as an evaporator. It is explanatory drawing which shows the refrigerant | coolant flow and air flow in a case.

FIG. 7 is an explanatory diagram schematically showing a connection state of heat transfer tubes according to the first embodiment of the present invention.

FIG. 8 is an explanatory view showing the configuration of the refrigerant path according to the first embodiment of the present invention.

FIG. 9 is a graph showing the refrigerant temperature change in the refrigerant flow direction and the air temperature change in the airflow direction according to Embodiment 1 of the present invention.

FIG. 10 is an explanatory diagram showing a coolant flow and an air flow when the heat exchange according to Embodiment 1 of the present invention is used as a condenser.

FIG. 11 is an explanatory diagram schematically showing a connection state of heat transfer tubes according to the first embodiment of the present invention.

FIG. 12 is an explanatory diagram showing the configuration of the refrigerant path according to the first embodiment of the present invention.

FIG. 13 is a graph showing the refrigerant temperature change in the refrigerant flow direction and the air temperature change in the airflow direction according to the first embodiment of the present invention.

FIG. 14 is a side configuration diagram showing another configuration example according to Embodiment 1 of the present invention.

FIG. 15 is an explanatory diagram schematically showing a connection state of heat transfer tubes according to the first embodiment of the present invention.

FIG. 16 is an explanatory diagram showing the configuration of the refrigerant path according to the first embodiment of the present invention.

圆 17] A graph showing the heat exchange capability according to the first embodiment of the present invention.

18] A graph showing the heat exchange capability according to the first embodiment of the present invention.

FIG. 19 is a flowchart showing a process of installing an indoor unit for heat exchange in connection with heat exchange according to Embodiment 1 of the present invention.

20] Description showing the state of heat exchange during assembly according to the first embodiment of the present invention. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1.

The configuration of the air conditioner according to Embodiment 1 of the present invention will be described below. Fig. 1 is an explanatory view showing the internal configuration of the heat exchanger according to Embodiment 1 of the present invention. Fig. 1 (a) is a front view, and Fig. 1 (b) is a cross-sectional view taken along line BB in Fig. 1 (a). FIG. A plurality of plate-like fins 1 are juxtaposed in parallel at a predetermined interval (fin pitch) Fp, and a heat transfer tube 2 is inserted at a substantially right angle to the fins 1 and fixed to the fins 1. Usually, the rows of the heat transfer tubes 2 extend in the longitudinal direction of the fins 1 and are provided in a plurality of rows in the airflow direction. Here, the heat transfer tubes 2 having two rows of heat transfer tubes 2a and 2b are illustrated. When air flows in a direction perpendicular to the paper surface of FIG. 1 (a), heat is exchanged with the refrigerant flowing in the heat transfer tube 1, and the temperature of the air rises or falls due to the hot or cold heat of the refrigerant. The fin 1 is in close contact with the heat transfer tube 2 and has the effect of increasing the heat transfer area. The direction of the adjacent heat transfer tubes 2 in one row is called a step, and as shown in Fig. 1, the step interval (step pitch) Dp, fin, which is the distance between the centers of adjacent heat transfer tubes in the step direction of the heat exchanger It is composed of 1 interval (fin pitch) Fp and fin thickness Ft. In this embodiment, for example, fin pitch Fp = 0.0012 m, fin thickness Ft = 0.0000095 m, and step pitch Dp = 0.2044 m.

FIG. 2 is a refrigerant circuit diagram showing an example of the refrigerant circuit of the air conditioner according to this embodiment, and shows an air conditioner having cooling and heating functions. In the refrigerant circuit shown in the figure, the compressor 10, the indoor heat exchanger 11, the expansion device 13, the outdoor heat exchanger 12, and the flow path switching valve 14 are connected by a connecting pipe. Circulate such refrigerant. In the indoor heat exchanger 11 and the outdoor heat exchanger 12, heat exchange between the air blown by the blower 5 that is rotationally driven by the blower motor 9 and the refrigerant is performed. The indoor heat exchanger 11 and the outdoor heat exchanger 12 are heat exchangers having the basic configuration shown in FIG.

[0011] The arrows in FIG. 2 indicate the flow direction of the refrigerant during heating. In this refrigeration cycle, the refrigerant gas compressed to high temperature and high pressure by the compressor 10 is condensed by heat exchange with room air through indoor heat exchange ll, and becomes a low-temperature high-pressure liquid refrigerant or gas-liquid two-phase refrigerant. At this time, heating to warm indoor air is performed. After that, the pressure is reduced by the expansion device 13 and flows into the outdoor heat exchanger 12 as a low-temperature low-pressure liquid refrigerant or a gas-liquid two-phase refrigerant. Evaporates by exchanging heat with outdoor air Then, it becomes high-temperature and low-pressure refrigerant gas and circulates again to the compressor 10.

During cooling, the connection of the flow path switching valve 14 is switched as shown by the dotted line, and the refrigerant is circulated to the compressor 10—> outdoor heat exchange 12—> expander 13—> indoor heat exchange 11—1> compressor 10. The refrigerant is condensed in the outdoor heat exchanger 12 and evaporated in the indoor heat exchanger 11. When the indoor heat exchanger 11 evaporates, the room air is cooled.

Normally, the indoor heat exchanger 11, the blower 5 and the blower motor 9 are stored in one housing and installed indoors as the indoor unit, and the other parts, that is, the compressor 10, the flow path switching valve 14, and the outdoor heat exchange. Unit 12, fan 5 and fan motor 9 are installed as outdoor units outside the room, and the indoor unit and the outdoor unit are connected by refrigerant piping.

[0012] The energy efficiency of the air conditioner is expressed by the following equation.

Heating energy efficiency = indoor heat exchanger (condenser) capacity, all inputs

Cooling energy efficiency = indoor heat exchanger (evaporator) capacity, all inputs

That is, if the heat exchange capacity of the indoor heat exchanger 10 and the outdoor heat exchanger 12 is improved, an air conditioner with high energy efficiency can be realized. In this embodiment, an attempt is made to improve the heat exchange capacity of a heat exchanger, particularly an indoor unit.

[0013] FIG. 3 is a side view showing an indoor unit of an air conditioner equipped with heat exchange according to this embodiment, and is attached to the wall surface of the room at the right side as opposed to the drawing of the housing. . The indoor unit of the air conditioner of this embodiment has a height of 0.3 m and a depth of 0.225 m, for example, and the heat exchanger 15 is divided into two in the direction of gravity, and the upper heat exchanger 15a and It consists of the lower heat exchanger 15b. The heat exchanger tubes 2 of the heat exchangers 15a and 15b form two rows, an upwind row and a leeward row in the direction of airflow flowing from the inlet 8 to the outlet 6, and each row consists of six stages of heat exchanger tubes. ing. These heat exchangers ^^ 15a and 15b are arranged in an angle with each other in the shape of a “<” and are arranged so as to surround the blower 5 on the suction port 8 side of the blower 5. An insulation 17 is provided between the heat exchanger 15a and the air to prevent air flow through the gap. 18, 19 a, 19 b are the refrigerant inlet and outlet to the heat exchanger 15, 18 is the windward upstream refrigerant port provided in the windward upstream heat transfer tube, and 19 a, 19 b is provided in the windward downstream heat transfer tube These are the two coolest down-stream refrigerant ports, V, and the misalignment is arranged in the center of the fin 1 in the longitudinal direction.

[0014] Fin width L is the same in both upper heat exchanger 15a and lower heat exchanger 15b. For example, L = 0.0254 m. The heat transfer tube 2 is inserted into a hole provided in advance in the fin 1 in a state 3 (hereinafter referred to as a hairpin 3) folded into a U-shape as shown in FIG. 4, for example, by expanding the heat transfer tube 2 and the fin 1 Adhere closely. On the side opposite to the side where the hairpin 3 is inserted, the U-bends 4a, 4b and the three-way bend 16 are connected to the end of the hairpin 3 to form a refrigerant flow path. The side configuration shown in Fig. 3 shows the side where U-bends 4a, 4b and 3-way bend 16 are connected, and hairpin 3 is inserted and fixed on the opposite side of Fig. 3. The heat transfer tube 2 and the dotted line form a U-shaped hairpin 3. U-bends 4a and 4b are different in length, U-bend 4a is a pipe that connects the heat transfer tubes in the same row in the step direction, and U-bend 4b is a heat transfer tube in a different row in the row direction. It is a pipe to be connected.

Heat exchanger 15 is divided into two parts by upper heat exchanger 15a and lower heat exchanger 15b.

That is, the separation means 21 that thermally separates the upper and lower sides by the space that can be divided in the longitudinal direction of the fin 1 by dividing the heat exchange is configured. Where fin width L is upper heat exchanger 1

Preferably there is. However, they may not be the same for manufacturing reasons. For example, about ± lmm, even if there is a difference between the fin width of the upper heat exchanger 15a and the width of the lower heat exchanger 15b, it can be regarded as equivalent.

[0015] Further, the front portion of the casing does not transmit air, for example, and uses the front panel 7 to rotate the blower 5 with the blower motor 9 so that it can be emptied from the suction port 8 disposed above the indoor unit. The air is sucked and guided into the air passage, and blown out from the outlet 6 provided below the indoor unit. The plurality of fins 1 constituting the heat exchanger 15 are arranged in parallel in the direction of the rotation axis of the blower 5 at a predetermined interval (fin pitch FP).

FIGS. 5 (a), (b), and (c) are a front view, a right side view, and a bottom view showing a three-way bend 16 that is an example of a branch pipe provided at a branch portion of a refrigerant circuit. In the figure, 20 indicates a branching portion. The three-way bend 16 is, for example, one pass.> The two-pass branch 20 and three connections connected to the end of the heat transfer tube 2, i.e., the hairpin 3, are divided into these three directions. The flow path from the section 20 to the connection section connected to the heat transfer pipe 2 is called the connection pipe, and the short connection pipes 16a and 16b are connected to the long connection pipe. It consists of tube 16c. Then, the connection pipe 16b is connected to the heat transfer pipe 2 in the one-pass portion, and the connection pipe 16a and the connection pipe 16c are connected to the heat transfer pipe 2 in the two-pass portion.

Here, as shown in Figure 3,

Are connected across. In other words, the long connecting pipe 16c on the lower side in the gravitational direction, the short connecting pipes 16a and 16b on the upper side in the gravitational direction, the end of the long and connecting pipe 16c are connected to the lower heat exchanger 15b, and the short connecting pipe 16a. And connect the end of 16b to the upper heat exchanger 15a. As a refrigerant flow path, a long connection pipe 16c is connected to one of the two paths. Then, one of the short connection pipes 16a and 16b is connected to one path part, and the other is connected to the remaining path of the two path parts.

[0017] In this embodiment, the heat exchanger tube 2 is configured to have a branching portion 20 that partially increases or decreases the number of refrigerant flow paths, and the heat exchange 15 accommodated in a limited space The heat exchange performance varies greatly depending on whether the refrigerant flow path is constructed. If the number of passes is the same between the refrigerant inlet force and the refrigerant outlet without providing the branching section 20, the refrigerant flow path can be configured relatively simply, but if the branching section 20 is provided, multiple refrigerant flow paths are formed. It becomes a complicated structure. It is not easy to configure heat exchange with air efficiently in all of the plurality of refrigerant flow paths that pass through different paths at least partially. Here, the branch part 20 is provided to improve the heat exchange performance, and the state of the refrigerant flowing through a plurality of refrigerant flow paths formed between the refrigerant inlet and the refrigerant outlet, and the positional relationship between the air flow and the refrigerant flow path Examine the refrigerant flow and air flow, etc., and construct an air conditioner with good heat exchange performance by configuring heat exchange efficiently with a heat exchanger. In particular, the configuration of the fin tube type heat exchanger is such that the heat transfer tubes 2 extending in the direction of the rotation axis of the blower 5 are arranged side by side in a plurality of rows, and the heat transfer tubes are arranged on the side of one heat exchanger. Depending on how the respective end portions of 2 are connected, the configuration of the refrigerant flow path is determined. Under such conditions, it is required to obtain an air conditioner with excellent heat exchange performance.

[0018] As described in FIG. 2, when the air conditioner has a cooling function and a heating function, the heat exchanger is used as both a condenser and an evaporator, and the refrigerant flow path in the heat exchanger 15 is The refrigerant inlet and refrigerant outlet are reversed. Hereinafter, a description will be given of a case where the air conditioner is cooled and the heat exchanger 15 is operated as an evaporator. FIG. 6 is an explanatory view showing a refrigerant flow and an air flow when the heat exchanger of this embodiment is used as an evaporator, and FIG. 7 is an explanatory view schematically showing a connection state of heat transfer tubes. When the heat exchanger 15 is operated as an evaporator, the windward upstream refrigerant port 18 is the refrigerant inlet, and the coldest row refrigerants 19a and 19b are the refrigerant outlets.

As the blower 5 rotates, the air flowing from the suction port 8 flows between the fins 1 of the heat exchanger 15 as shown in FIG. 6, exchanges heat with the refrigerant flowing through the heat transfer tube 2, and flows out from the blower outlet 6. Here, since a fixed panel that does not transmit air is used for the front panel 7, the air flow in the indoor unit is high on the upper side of the heat exchanger 15 and low on the lower side. The heat transfer tube indicated by a dark circle in the upper heat exchanger 15a in FIG. 6 is a portion where the refrigerant flowing inside may be in a dry state. A heat tube was used. Similarly, in the lower heat exchanger l5b, there is a possibility that the refrigerant will dry out with several heat transfer tubes for the refrigerant outlet side force. Figure 7 shows the heat transfer tube display in the order of row number and upward force. For example, heat transfer tube D11 is represented as the first heat transfer tube from the top in the windward row, and heat transfer tube D21 is represented as the first heat transfer tube from the top in the leeward row. Here, the refrigerant inlet is the sixth heat transfer tube D16 in the windward row, and the refrigerant outlet is the sixth heat transfer tube D26 in the leeward row and the seventh heat transfer tube D27 in the leeward row.

FIG. 8 is an explanatory diagram showing the configuration of the refrigerant path. For example, in the configuration of this embodiment, the refrigerant inlet is connected to the 1-pass portion R1, flows through the 1-pass portion R1 for 4 heat transfer tubes, branches to the 2-pass portions R21 and R22, and R21 is 8 heat transfer tubes. , R22 connects to the refrigerant outlet in 12 bottles. The black circles in the two-pass sections R21 and R22 indicate the part connected from the heat transfer tubes in the windward row to the heat transfer tubes in the leeward row.

[0020] When the heat exchanger 15 is operated as an evaporator, a two-phase refrigerant with a high liquid ratio and a low gas ratio flows at the refrigerant inlet of the heat exchanger 15 and evaporates as it flows through the heat transfer tube 2. Gradually, the proportion of gas increases, and when it exceeds the saturation state, it becomes overheated and flows to the refrigerant outlet. One pass in the vicinity of the refrigerant inlet has a great effect when operated as a condenser, but this will be described later. In the case of an evaporator, comparing the 1-pass part R1 with the refrigerant inlet and the 2-pass parts R21 and R22 with the refrigerant outlet, the pressure loss in the 1-pass part R1 is larger than that in the 2-pass parts R21 and R22. The power of two-phase refrigerant gas The flow rate is slower in the portion where the ratio is small compared to the portion where the gas ratio is high. For this reason, even if the portion of the gas near the refrigerant inlet is small and the 1-pass portion R1 is used, the pressure loss does not increase as much as 1 pass in the portion where the flow velocity is high. Furthermore, the refrigerant flow path where the two-phase refrigerant flows is branched into two-pass sections R21 and R22 to reduce pressure loss. If the pressure loss is reduced in the 2-pass section, the burden on the compressor 10 can be reduced.

FIG. 9 is a graph showing the refrigerant temperature change in the refrigerant flow direction and the air temperature change in the airflow direction by the heat exchanger 15 configured as shown in FIGS. The horizontal axis indicates the position in the flow direction of air or refrigerant, and the vertical axis indicates the temperature. On the refrigerant side, the temperature of the refrigerant flowing into the heat transfer tube D16 is the refrigerant inlet temperature, and the temperature of the refrigerant flowing out of the heat transfer tubes D26 and D27 is the refrigerant outlet temperature. During this time, the refrigerant in the gas-liquid two-phase state gradually evaporates and becomes saturated or slightly overheated, but the refrigerant temperature decreases as it goes from the inlet to the outlet due to the pressure drop due to the pressure loss in the pipe. . On the other hand, on the air side, the black circle P1 neighborhood in Fig. 6 is the air inlet, the black circle P2 neighborhood is the air outlet, and it is cooled by heat exchange ^^ 15 while flowing from the inlet P1 to the outlet P2, and the air temperature is Decrease from P1 to exit P2.

[0022] The refrigerant flow will be described in more detail below.

As shown in FIG. 7, the refrigerant flowing from the lowermost heat transfer tube D16 in the upwind row of the upper heat exchanger 15a passes through the one-pass portions D16 to D13 of the upper heat exchanger 15a, and becomes a three-way bend 16. It flows in and is divided into two paths by this branch. One short connection pipe 16a is connected to the heat transfer pipe D12 of the upper heat exchanger 15a, flows into the leeward line when flowing from the heat transfer pipe D11 to the heat transfer pipe D21, and flows to the refrigerant outlet through D21 to D26. . That is, as shown in FIG. 8, the refrigerant passes from the refrigerant inlet to the refrigerant outlet through the 1-pass portion R1 and the 2-pass portion R21, and flows through the heat transfer tube 2 of 12 lengths. Here, the flow path between the refrigerant inlet and the refrigerant outlet is referred to as an upper refrigerant flow path.

[0023] The other long connecting pipe 16c divided into two paths at the branch portion of the three-way bend 16 is connected to the heat transfer pipe D17 of the lower heat exchanger 15a, passes through the heat transfer pipe D17 to the heat transfer pipe D112, and passes through the heat transfer pipe. When flowing to D 212, it flows into the leeward row and flows to the refrigerant outlet through D212 to D27. That is, as shown in FIG. 8, the refrigerant inlet force also passes through the 1-pass part R1 and the 2-pass part R22 to the refrigerant outlet and flows through the heat transfer tube 2 of 16 lengths. Here, the flow path between the refrigerant inlet and the refrigerant outlet is lowered. This is referred to as a side refrigerant flow path.

In both the upper and lower refrigerant channels, each of the branched refrigerants is arranged in a direction perpendicular to the air flow direction, and the upwind row hairpins 3 and U-bends 4a. Flowing. Then, it flows in the U-bend 4b arranged in parallel to the airflow direction in a direction substantially parallel to the airflow, flows through the hairpin 3 and U-bend 4a in the leeward row, and then flows out from the refrigerant outlets 19a and 19b. The refrigerant flow path is configured by connecting the heat transfer tubes so that the refrigerant never flows in the direction of the airflow once again throughout the refrigerant flow path.

[0024] In the heat exchanger configured as shown in Fig. 6, the refrigerant flows in the respective refrigerant flow paths of the upper refrigerant flow path and the lower refrigerant flow path. Flows sequentially in the direction. For this reason, as shown in FIG. 9, the refrigerant temperature change monotonously decreases toward the refrigerant inlet force toward the refrigerant outlet, and is generally parallel to the air temperature change. As a result, the temperature difference between the air temperature and the refrigerant temperature is always kept uniform, and heat exchange between the refrigerant and air can be performed efficiently in any part of the heat exchange, so the heat exchanger capacity can be improved and energy efficiency can be improved. High air conditioner.

If the air temperature change and refrigerant temperature change in Fig. 9 are not parallel and change so that they are partly apart and approach partly, the temperature will be too close at the part that is approaching, and heat will be generated between the air temperature and the refrigerant temperature. Cannot be exchanged. In this case, the heat exchange ability is adversely affected. If the air temperature change and the refrigerant temperature change are made parallel to this, the heat exchange ability can be improved. Here, as for the temperature difference between the air temperature change and the refrigerant temperature change, the smaller the difference, the higher the heat transfer coefficient, and the greater the difference in heat transfer capacity. At least, by configuring the air temperature change and the refrigerant temperature change in parallel, the heat exchanger capacity can be improved, and an air conditioner with high energy efficiency can be obtained.

[0025] As shown in FIG. 8, each of the plurality of refrigerant flow paths has only one portion flowing from the first windward row indicated by a black circle to the second leeward row. According to this configuration, the refrigerant flowing through the refrigerant flow paths of the upper refrigerant flow path and the lower refrigerant flow path sequentially flows in one direction from the windward heat transfer pipe to the leeward heat transfer pipe. The temperature change on the refrigerant side decreases monotonously from the refrigerant inlet to the refrigerant outlet, and is almost parallel to the temperature change on the air side.

[0026] In this way, branching that partially increases or decreases the number of refrigerant flow paths by the heat transfer tubes 2 The refrigerant flowing through each of the plurality of refrigerant flow paths provided with the pipe 16 and passing through different paths at least partly between the refrigerant inlet 18 and the refrigerant outlets 19a and 19b flows from the windward line to the leeward line. In this way, heat transfer performance is improved by efficiently exchanging heat at any part of the heat exchange ^^, resulting in an air conditioner with high energy efficiency. It is done.

[0027] It should be noted that the configuration of the refrigerant flow path shown here is merely an example, and is not limited to this! /. In the heat exchanger 15 used as an evaporator, the refrigerant inlet is one of the windward heat transfer tubes, the refrigerant outlet is one of the two windward heat transfer tubes, and the 1-pass section R1 is not wind across multiple lines. Only the upper row heat transfer tube. In all of the plurality of refrigerant flow paths configured, the cooling medium is configured to flow in one direction from the leeward row to the leeward row without returning backward between the rows (leeward row> upwind row). That's fine. As a result, the air temperature change and the refrigerant temperature change can be made substantially parallel, and heat exchange can be efficiently performed at any part of the heat exchanger 15 to improve the heat transfer performance.

[0028] Further, in each of the plurality of refrigerant flow paths, it is preferable to lengthen the length of the heat transfer tube to the local force refrigerant outlet flowing into the leeward row to some extent. When the refrigerant flowing through the refrigerant flow path is overheated near the refrigerant outlet, the phenomenon of drying close to the air temperature occurs and the heat transfer performance deteriorates. If the refrigerant flowing through both the windward and leeward heat transfer tubes located near the passage of an air flow is overheated, the air is hardly cooled and the high-temperature and high-humidity air is not cooled. It flows into the blower 5 as it is. For example, when the refrigerant flowing through both the heat transfer tube D11 and the heat transfer tube D21 in the upper heat exchanger 15a is in an overheated state, the air flow flowing through this portion flows into the blower 5 as high-temperature and humid air. However, some of the air flowing into the blower 5 is sufficiently dehumidified through other parts of the heat exchange to become low-temperature and low-humidity air. For this reason, in the space from the inside of the blower 5 to the outlet 6, the high-temperature and high-humidity air is cooled to the low-temperature and low-humidity air to cause condensation, and water droplets are scattered from the outlet 6 together with the outlet air.

On the other hand, if the length of the heat transfer tube from the part flowing into the leeward line to the refrigerant outlet is increased to some extent in each of the upper refrigerant flow path and the lower refrigerant flow path, the refrigerant will be overheated. It can only be a leeward heat transfer tube, at least a cold flow through the windward heat transfer tube. Since the medium becomes a two-phase state or a saturated state, it becomes low-temperature and low-humidity air when passing through the heat-upward heat transfer tube. For this reason, it is possible to prevent the hot and humid air from flowing into the blower 5 and to prevent water droplets from being scattered from the outlet 6.

[0029] Here, for example, in the upper refrigerant flow path, the diagonal U-bend section connecting the upwind row D11 and the downwind row D21 also has six heat transfer tubes to the refrigerant outlet of the leeward row D26, that is, the entire 1Z4 It was. Similarly, the number of heat transfer tubes from the oblique U-bend portion connecting the windward row D112 and the leeward row D212 to the refrigerant outlet of the leeward row D27 is six in the lower refrigerant flow path. When operating the refrigeration cycle, the 1Z4 heat transfer tube of the entire heat transfer tube is almost never overheated, but here the six heat transfer tubes near the outlet in the upper refrigerant flow path, that is, the entire 1Z2 Arranged in the leeward row, six heat transfer tubes near the outlet in the lower refrigerant flow path, that is, the entire 3Z8, were placed in the leeward row. In each refrigerant flow path, even if the refrigerant is overheated by the six heat transfer tubes of the leeward heat transfer tube, the two-phase refrigerant always flows in the windward heat transfer tube, and the airflow heat transfer tube and the leeward heat transfer tube Both can be prevented from being overheated. Therefore, even when the phenomenon of overheating at the refrigerant outlet and drying close to the air temperature occurs, the humid air is dehumidified by the refrigerant in the windward heat transfer tube, so the high-temperature and high-humidity air and the low-temperature and low-humidity air are heat exchangers 15 It is possible to prevent the occurrence of dew condensation that occurs after mixing after flowing out of the water.

[0030] In this manner, the refrigerant flowing in at least one of the heat transfer tubes in different rows located in the vicinity of the airflow passage is in a two-phase refrigerant state, that is, a saturated refrigerant state. By configuring this refrigerant flow path, it is possible to obtain an air conditioner that can prevent the occurrence of dew condensation in the air path in the indoor unit and can prevent the water droplets from being scattered.

In particular, it is provided with an upwind row refrigerant B 18 provided in the heat transfer tube 2 in the center of the most windward row, and downwind row refrigerants 19a and 19b provided in the heat transfer tube 2 in the center of the most downwind row, By connecting the heat transfer tubes D21, D212 at the end in the longitudinal direction of the windward row to the heat transfer tubes Dl l, 0112 in the row adjacent to the windward row with 11-bend 4b, water droplets are prevented from splashing. A possible air conditioner is obtained.

[0031] Note that instead of increasing the length of the heat transfer tube from the inflow portion from the windward heat transfer tube to the leeward heat transfer tube to the refrigerant outlet, the heat transfer tube 1S air in which the refrigerant near the refrigerant outlet may be overheated The refrigerant flow path may be configured so that the upwind heat transfer tube and the downwind heat transfer tube do not overlap the flow! That is, the air flowing into each part of the heat exchanger 15 exchanges heat in the windward row. If the refrigerant flow is configured by connecting the heat transfer tubes so that the refrigerant flowing through at least one of the heat transfer tubes of the windward heat transfer tubes and the leeward heat transfer tubes that exchange heat in the leeward row is in a two-phase state or a saturated state, Good. For example, when both the upwind heat transfer tubes and the leeward heat transfer tubes are overheated, the flow of the refrigerant in one of the heat transfer tubes may be exchanged with the other heat transfer tubes in the same row.

[0032] In particular, the wind speed of the air flow is fast! The refrigerant is easy to evaporate in the part! /, So the wind speed is fast! In the upper heat exchanger 15a, the refrigerant is overheated in the upwind and downwind heat transfer tubes. It is preferable to prevent the situation. That is, it is better to lengthen the length of the heat transfer tube 2 from the part that flows into the windward row to the refrigerant outlet 19a in the upper heat exchanger 15a where the wind speed is fast.

[0033] When the heat exchange 15 is arranged in the vertical direction as shown in FIG. 6, the refrigerant flowing through the U-turn portion, the U-bend 4 and the 3-way bend 16 of the hairpin 3 positioned in the vertical direction is gravity. to be influenced. That is, when the two-phase refrigerant that has also entered the refrigerant inlet force flows through the 1-pass section and flows through the short connecting pipe 16b and is distributed to the connecting pipe 16a and the connecting pipe 16c at the branch section, the liquid refrigerant It is arranged below the gravitational direction rather than flowing to 15a, so it tends to flow to the lower heat 5b. In this embodiment, in the three-way bend 16, which is a branch pipe, two connection pipes that branch from one path to two paths by arranging a short connection pipe 16a in the upper part of the gravity direction and a long connection pipe 16c in the lower part of the gravity direction. A difference was made in the pressure loss of 16a and 16c. That is, by making the connecting pipe 16c below the gravitational direction of the three-way bend 16 longer than the connecting pipe 16a to the other side, the pressure loss of the pipe is increased and the flow of the refrigerant does not easily flow to the connecting pipe 16c. For this reason, the two-phase refrigerant can be made to flow equally and heat exchange performance can be improved.

Here, if the branch pipe 16 has three or more connecting pipes, as in the case of 1-pass-> multiple paths, when increasing the number of passes, the heat transfer pipe downstream of the refrigerant flow Of the connecting pipes connected, the pressure loss when the refrigerant flows through the connecting pipe connected to the heat transfer pipe below the gravitational direction is greater than the pressure loss when the refrigerant flows through the connecting pipe connected to the heat transfer pipe above the gravitational direction. What is necessary is just to comprise a branch pipe so that it may become large.

[0034] Instead of making the connecting pipe 16c longer than the connecting pipe 16a, the connecting pipe 16c below the gravitational direction of the two-pass connecting pipes 16a and 16c of the three-way bend 16 is connected to the other by the other configuration. It may be larger than the pressure loss of the connecting pipe 16a. For example, within the connection piping 16c The pressure loss can be increased by providing grooves on the wall or providing small protrusions. By making a difference in the pressure loss and making it difficult for the refrigerant to flow through the pipe arranged below the gravity direction, the two-phase refrigerant can be branched almost equally at the branch portion.

[0035] Thus, the branch pipe 16 has the connection pipes 16a, 16b, 16c connected to the connection parts connected to the three or more heat transfer pipes 2 from the branch part 20 to increase the number of noses. Of the connection pipes 16a and 16c connected to the heat transfer pipe on the downstream side of the refrigerant flow, the pressure loss when the refrigerant flows through the connection pipe 16c connected to the heat transfer pipe below the gravitational direction is applied to the heat transfer pipe above the gravitational direction. By configuring the branch pipe 16 to be larger than the pressure loss when the refrigerant flows through the connecting pipe 16a to be connected, an equal distribution of the two-phase refrigerant is realized, the heat exchange performance is improved, and the energy is A highly efficient air conditioner can be obtained.

[0036] In particular, the length from the branch part 20 of the branch pipe 16 to the connection part connected to the heat transfer pipe 2 below in the gravitational direction, that is, the length of the connection pipe 16c is changed from the branch part 20 of the branch pipe 16 to the heat transfer pipe above the gravitational direction. By connecting the connection pipe to 2 or longer than the length of the connection pipe 16a, the pressure loss of the two connection pipes can be easily differentiated, and the equal distribution of the two-phase refrigerant can be easily realized. It can appear.

[0037] In the above, the force described for the configuration of branching from one path to one path is not limited to this. One path may be branched into multiple paths of> 3. It can also be applied to a case where two or more paths are branched into a plurality of paths of> 3.

Further, in the above description, the configuration has two rows of the windward heat transfer tube and the leeward heat transfer tube in the air flow direction, but may have a configuration having three or more heat transfer tube rows. In this case, for example, in three rows, the refrigerant flowing in each of the plurality of refrigerant flow paths between the refrigerant inlet and the refrigerant outlet flows in one direction between the rows from the windward row to the leeward row in the airflow direction. If it is configured to flow in the order of windward row> intermediate row 1> leeward row.

[0038] Further, when the configuration has three or more rows of heat transfer tubes, the refrigerant flowing in at least one of the heat transfer tubes of different rows located in the vicinity of the airflow passage is in a two-phase refrigerant state or If the refrigerant flow path is configured so as to be in a saturated refrigerant state, it is possible to prevent the hot and humid airflow from flowing into the blower 5 and to prevent water droplets from being scattered from the outlet 6.

When a plurality of refrigerant flow paths are formed, the lengths of the respective flow paths are configured to be equal. And it is preferable because heat exchange can be performed in a well-balanced manner as a whole. Here, the upper refrigerant flow path is equivalent to 12 heat transfer tubes, and the lower refrigerant flow path is equivalent to 16 heat transfer tubes.

[0039] Next, the case where the air conditioner is operated for heating and the heat exchange is operated as a condenser will be described. The configuration of the indoor unit is the same as that operated as an evaporator as shown in FIG. 3, but the inlet and outlet of the refrigerant flowing through the heat exchanger 15 are reversed, and the refrigerant flow direction is different from that of the evaporator. Vice versa.

Fig. 10 is an explanatory diagram showing the refrigerant flow and air flow when the heat exchanger of this embodiment is used as a condenser. The heat transfer tubes shown in dark circles are the internal parts at the outlet side of the refrigerant flow path. This is the part where there is a possibility that the refrigerant flowing into the supercooled state, and several heat transfer tubes from the refrigerant outlet side, for example, six heat transfer tubes are used here. FIG. 11 is an explanatory view schematically showing the connection state of the heat transfer tubes. When the heat exchanger 15 is operated as a condenser, the windward downstream refrigerant port 19a, 19b is the refrigerant inlet and the windward upstream refrigerant port 18 is the refrigerant outlet.

By the rotation of the blower 5, the air flowing from the suction port 8 flows between the fins 1 of the heat exchanger 15, exchanges heat with the refrigerant flowing through the heat transfer pipe 2, and flows out from the outlet 6. This air flow is the same as when operating as an evaporator, and the wind speed is high on the upper side of the heat exchange and low on the lower side. On the other hand, the refrigerant flow is the reverse of operating as an evaporator, and the refrigerant inlet is the sixth heat transfer tube D26 in the leeward row and the seventh heat transfer tube D27 in the leeward row, which are the leeward row refrigerant ports. The outlet is the 6th heat transfer tube D16 in the windward row, which is the most upwind refrigerant port.

[0040] FIG. 12 is an explanatory diagram showing the configuration of the refrigerant path. For example, in the configuration of this embodiment, the refrigerant inlet is connected to the two-pass portions R21 and R22, R21 is equivalent to eight heat transfer tubes, and R22 is equivalent to one two. It flows through the 1-pass section R1 for 4 pipes and connects to the refrigerant outlet. The black circles in the two-pass sections R21 and R22 indicate the part connected from the leeward heat transfer tube to the upwind heat transfer tube.

[0041] When the heat exchanger is operated as a condenser, the refrigerant enters the heat exchanger 15 in the superheated steam state, that is, with steam having a temperature higher than the refrigerant saturation temperature. This overheating zone has a small effect on the performance of the short comparative heat exchanger. After this, the refrigerant is cooled and reaches the saturation temperature. Then, the refrigerant enters a saturated state, for example, a two-phase state. Two-phase refrigerant has a very high heat transfer coefficient and accounts for most of the heat exchange. When the refrigerant becomes dryness (= vapor mass rate Z liquid mass rate) or less, it becomes a liquid single-phase state called supercooling. When supercooling is applied, the heat transfer rate is greatly deteriorated compared to the two-phase region, and the capacity of the heat exchanger is reduced, so that the pressure on the discharge side of the compressor increases and the compressor input increases. There are evil elements. On the other hand, if supercooling is applied, the enthalpy difference at the entrance and exit of the heat exchanger increases, increasing the amount of heat exchange. For this reason, it becomes possible to reduce the frequency of the compressor, and if the input of the compressor can be reduced, there is an effect of improving the heating energy efficiency. The air conditioner is operated by determining the best degree of supercooling (= saturation temperature and heat exchanger outlet temperature) in consideration of these energy efficiency factors and improvement factors.

As mentioned above, this is the cause of reducing the heat exchange performance where the heat transfer coefficient is low in the supercooled part near the refrigerant outlet, so in order to increase the flow velocity in the part where the supercooled refrigerant flows

1 pass part R1. Comparing the 1-pass part R1 and the 2-pass parts R21, R22 of the refrigerant flow path, the pressure loss in the 2-pass part R21, R22 is smaller than that in the 1-pass part Rl. It will increase slightly. However, the refrigerant in this part is undercooled and the amount of gas loss is smaller than the increase in pressure loss in the part of the two-phase refrigerant. The performance improvement effect is obtained. That is, in the part where the refrigerant flows in a saturated state or an overheated state, the refrigerant flow path is configured by the two-pass portions R21 and R22 to reduce pressure loss, reduce the burden on the compressor 10, and reduce the pressure around the refrigerant outlet. In the part that flows in the supercooled state, the refrigerant flow path is formed by the 1-pass part R1 to improve the heat exchange performance. FIG. 13 is a graph showing the refrigerant temperature change in the refrigerant flow direction and the air temperature change in the airflow direction due to the heat exchange 15 configured as shown in FIGS. The horizontal axis shows the position in the flow direction of air or refrigerant, and the vertical axis shows the temperature. Regarding the refrigerant side, the temperature of the refrigerant flowing into the heat transfer tubes D26 and D27 is defined as the refrigerant inlet temperature, and the temperature of the refrigerant flowing out of the heat transfer tube D16 is defined as the refrigerant outlet temperature. During this time, the refrigerant gradually condenses and becomes a supercooling zone through the superheated state two-phase region.The refrigerant temperature decreases in the superheating and supercooling regions, and the phase changes at a nearly constant temperature in the two-phase region. To do. On the other hand, on the air side, the black circle P1 neighborhood in Fig. 10 is the air inlet, the black circle P2 neighborhood is the air outlet, and the heat exchanger 15 is used during the flow from inlet P1 to outlet P2. As a result, the air temperature rises from the inlet PI to the outlet P2.

[0043] Hereinafter, the flow of the refrigerant will be described in more detail.

As shown in FIG. 11, the refrigerant flowing from the lowermost heat transfer tube D26 in the leeward row of the upper heat exchanger 15a passes through the two-pass portions D26 to D21 of the upper heat exchanger 15a and transfers heat from the heat transfer tube D21. As it flows into pipe D11, it flows into the windward line. Furthermore, it flows into the heat transfer tube D12, flows into the 3-way bend 16, merges, and flows into the 1-pass section. The short connection pipe 16a is connected to the heat transfer pipe D12 of the upper heat exchanger 15a, passes through the connection pipes 16a and 16b, and flows to the refrigerant outlet through D13 to D16. That is, as shown in FIG. 12, the refrigerant inlet force also passes through the two-pass portion R21 and the one-pass portion R1 to the refrigerant outlet and flows through the heat transfer tube 2 having a length of twelve. Here, the flow path between the refrigerant inlet and the refrigerant outlet is referred to as an upper refrigerant path.

[0044] On the other hand, the refrigerant flowing from the uppermost heat transfer tube D27 in the leeward row of the lower heat exchanger 15b passes through the two noses D27 to D212 of the lower heat exchange ^^ 15b, and the heat transfer tube D212 is used as the heat transfer tube. As it flows to D112, it flows into the windward line. Furthermore, it flows into the heat transfer tube D17, flows into the three-way bend 16, merges, and flows into the 1-pass section. The long connecting pipe 16c is connected to the heat transfer pipe D17 of the lower heat exchanger 15b, passes through the connecting pipes 16c and 16b, and flows to the refrigerant outlet through D13 to D16. That is, as shown in FIG. 12, from the refrigerant inlet to the refrigerant outlet, the two-pass portion R22 and the one-pass portion R1 pass through the heat transfer tube 2 having a length of 16 pipes. Here, the flow path between the refrigerant inlet and the refrigerant outlet is referred to as a lower refrigerant flow path.

In the upper refrigerant flow path and the lower refrigerant flow path, the refrigerant flowing in from the refrigerant inlets 19a and 19b is arranged in a direction perpendicular to the air flow direction and flows through the hairpin 3 and the U-bend 4a in the leeward row. Then, it flows in the U-bend 4b, which is arranged in parallel with the airflow direction, in a direction almost opposite to the airflow, flows through the hairpin 3 and U-bend 4a in the windward row, and then passes through the 3-way bend 16 And flows out from the refrigerant outlet 18. The refrigerant flow path is configured by connecting the heat transfer tubes so that the refrigerant does not flow in parallel with the air flow direction over the entire refrigerant flow path.

[0045] In the heat exchanger configured as shown in Fig. 10, the refrigerant flows in the respective refrigerant flow paths of the upper refrigerant flow path and the lower refrigerant flow path. Flows sequentially in the direction. For this reason, as shown in FIG. 13, the refrigerant temperature change almost monotonously decreases as the refrigerant inlet force also moves toward the refrigerant outlet, and is almost parallel to the air temperature change. As a result, air temperature and cold The temperature difference of the medium temperature is always kept uniform, and heat exchange between the refrigerant and air is performed efficiently in any part of the heat exchange, so the heat exchanger capacity can be improved and energy efficient air conditioning A machine is obtained.

[0046] As shown in FIG. 12, the configuration is such that each of the plurality of refrigerant flow paths has only one portion flowing from the second leeward row indicated by a black circle to the first leeward row. In this case, the refrigerant flowing through the refrigerant flow paths of the upper refrigerant flow path and the lower refrigerant flow path sequentially flows in one direction from the leeward heat transfer pipe to the upwind heat transfer pipe. For this reason, the temperature change on the refrigerant side decreases monotonously from the refrigerant inlet to the refrigerant outlet, and is substantially parallel to the temperature change on the air side.

[0047] When the refrigerant flow path is configured to reciprocate a plurality of times by the upwind heat transfer tube and the downwind heat transfer tube, the supercooling zone enters the downwind heat transfer tube and the upwind heat transfer tube and the wind Both refrigerants flowing in the lower row heat transfer tubes may be in a supercooled refrigerant state. At this time, the air passes through only the supercooling zone and blows out, and the heat exchange capacity decreases. In addition, even if the air does not pass through only the supercooling zone and blows out, if there is a place where the temperature difference between the air and the refrigerant is large, the heat exchange capacity will be reduced. Here, the refrigerant flow flows in one direction from the downwind row to the upwind row, so that the refrigerant flow does not flow parallel to the air flow direction. For this reason, the air temperature change and the refrigerant temperature change can be made substantially parallel, and the temperature difference can be made uniform, so that the heat exchange ability can be improved.

In this manner, the branch pipe 16 connected to the heat transfer pipe 2 and partially increasing or decreasing the number of paths of the refrigerant flow path by the heat transfer pipe 2 is provided, and at least between the refrigerant inlets 19a and 19b and the refrigerant outlet 18 The refrigerant flowing through each of the plurality of refrigerant flow paths formed so as to pass through different paths in part is configured so that the leeward row force in the airflow direction flows in sequence in one direction between the rows in the upwind row. By efficiently exchanging heat at any part of the heat exchange, heat transfer performance is improved, energy efficiency is high, and an air conditioner can be obtained.

[0049] The configuration of the refrigerant flow path shown here is an example, and the present invention is not limited to this. In the heat exchanger 15 used as a condenser, the refrigerant inlet is one of two locations on the leeward row heat transfer tube, the refrigerant outlet is the force on the windward row heat transfer tube, and the 1-pass section R1 is winded across multiple rows. The upper row heat transfer tube only. In all of the plurality of refrigerant flow paths configured, the refrigerant flows from the leeward row to the windward row without going back in the reverse direction (upwind row 1> leeward row) between the rows. What is necessary is just to comprise so that it may flow in order. As a result, the change in the air temperature and the change in the refrigerant temperature can be made substantially parallel, and heat exchange can be efficiently performed at any part of the heat exchange to improve the heat transfer performance.

[0050] Further, in the heat exchanger of this embodiment, the one-pass portion is arranged in a portion of the upper heat exchanger 15a near the lowermost portion of the windward row where the wind speed is high. For this reason, the supercooling of the refrigerant can be increased and the amount of heat exchange can be increased. In particular, the supercooling of the refrigerant is increased by utilizing the part where the wind speed is high, so that a large amount of supercooling can be obtained with a small number of heat transfer tubes, and the heat exchange capacity is improved.

[0051] As described above, the branch pipe 16 is configured such that the number of passes is increased or decreased in the 1-pass portion and the multiple-pass portions, and the 1-pass portion R1 is arranged in the most upwind row in the airflow direction, thereby The subcooling can be increased and the amount of heat exchange can be increased.

[0052] The refrigerant temperatures at the inlet A and the refrigerant outlet B of the one-pass portion in FIG. 10 are shown in A and B in the supercooling region of the refrigerant temperature change in the graph of FIG. The temperature difference between the refrigerant outlet B provided at the lowermost part of the upper heat exchanger 15a and the three-way bend 16 connection A of the lower heat exchanger 15b is a supercooling region, so it is very large compared to the two-phase region. Therefore, in this embodiment, the heat exchanger is configured such that the fins are separated by the upper heat exchanger 15a and the lower heat exchanger 15b. That is, the 3-way bend 16 is connected so as to straddle the two heat exchanges ^^ 15a, 15b, the heat transfer tube D17 of the 3-way bend 16 connection part A is provided in the lower heat exchanger 15b, and the heat transfer tube of the refrigerant outlet B D16 was installed in the upper heat exchanger 15 _& . For this,

As a result, the fins where the heat transfer tubes with a large temperature difference between A and B are separated from each other thermally, and heat is not transferred to each other, so heat loss can be prevented and heat exchange capacity is improved. .

[0053] As described above, when the heat exchange is operated as a condenser, the multi-pass force of the refrigerant flow path is also reduced to one pass, and each of the fin and the multi-pass closely contacting the heat transfer tube in the vicinity of the refrigerant outlet is used. The heat exchange capability can be improved by thermally separating the heat transfer tubes located in the most downstream from the fins that are in close contact with the heat transfer tubes located closest to the refrigerant outlet.

In addition,

The parts having a large temperature difference are thermally separated from each other, but the present invention is not limited to this. Thermal For example, even if the upper heat exchanger 15a and the lower heat exchanger 15b are integrally formed as the separating means 21, and a groove or a thermal shield is provided in the fin between the supercooling inlet A and the refrigerant outlet B, they are mutually connected. It can be thermally separated, heat loss can be prevented, and heat exchange capability can be improved.

In addition, the supercooling zone and other zones, especially the outlet part of the supercooling zone and the two-phase zone or superheat zone, are thermally separated from each other. Can be prevented and the heat exchange capacity can be improved. Therefore, if a cut-off slit is provided in the fin 1 between the windward and leeward heat transfer tubes in the portion where the temperature difference is large, that is, in the direction extending in the longitudinal direction of the fins 1 between the heat transfer tube rows, the heat transfer tube rows They can be thermally separated from each other, improving the heat exchange performance.

Also, by forming the heat exchanger 15 integrally, compared to a configuration in which the heat exchanger is divided into an upper heat exchanger 15a and a lower heat exchanger 15b, the fin is easy to manufacture and easy to handle even in the manufacturing process. be able to.

[0054] As described above, when the heat exchanger 15 is operated as a condenser, the refrigerant flow path is reduced from the multiple pass portions R21, R22 to the single pass portion R1, and is closely attached to the heat transfer tube 2 at the refrigerant outlet 18. And fins that are in close contact with the heat transfer tube 2 (D17) located closest to the refrigerant outlet 18 among the heat transfer tubes 2 (D12, D17) located on the most downstream side of each of the multiple path portions R21, R22. By thermally separating, heat loss can be prevented in the heat transfer tube 2 having a large temperature difference, here, the fins of the heat transfer tube D17 and the heat transfer tube D16, and heat exchange capability can be improved.

[0055] In addition, the heat exchange 15 arranged on the front side of the blower 5 is configured by arranging two heat exchanges ^^ 15a and 15b in which the shape of the fin 1 is substantially equivalent in a "<" shape. As a result, it becomes easy to manufacture, and it is possible to easily realize a thermal separation configuration, thereby improving the heat exchange capability.

The heat exchange is composed of an upper heat exchange l5 _a and a lower heat exchange b separated vertically, and the refrigerant outlet 18 when the heat exchanger 15 is operated as a condenser is connected to the gravity of the upper heat exchanger 15a. At least one of the connection pipes 16a, 16c connected to the upstream side of the refrigerant flow among the connection pipes 16a, 16b, 16c of the branch pipe 16 and provided in the heat transfer pipe 2 (D16) located at the lowest direction Piping, in this case the connecting pipe 16c, is arranged in the lower heat exchanger 15b, so that a thermal separation configuration can be easily realized and the heat exchange capacity is improved. It can be done.

[0056] In addition, for example, the refrigerant 1S airflow direction that flows through each of a plurality of refrigerant flow paths formed between the refrigerant inlet 18 and the refrigerant outlets 19a and 19b so as to pass through different paths at least partially. For example, a part of the refrigerant that flows through one of the refrigerant flow paths and flows backward between the rows in a configuration in which the windward to leeward row or the leeward row to the windward row flows in one direction between the rows. Even if there is a problem, it is possible to achieve some effects by configuring as follows.

In other words, by setting a part of the windward upstream heat transfer tube as a 1-pass section R1, it is possible to increase the supercooling when the heat exchange 15 is operated as a condenser with one path at a high wind speed. , Heat exchange performance can be improved. Further, as the separation means 21 that thermally separates up and down in the longitudinal direction of the fin 1 at least on the windward side of the fin 1, here, the heat exchange 15 is separated into an upper heat exchange 15a and a lower heat exchange l5b. Connecting pipe 16a, heat transfer pipe 2 connected to 16c

It was configured to be thermally separated. This makes it possible to thermally separate the fins 1 that are in close contact with the heat transfer tube, which becomes a supercooling part when operating as a condenser and has a large temperature difference, thus reducing thermal loss at the fins 1 and heat exchange. An air conditioner that can improve performance is obtained.

Note that the separation means can achieve the same effect as described above even if a notch that vertically separates in the airflow direction at least at the windward portion of the fin 1 and is thermally separated vertically in the longitudinal direction of the fin 1. .

[0057] In this way, the leeward row refrigerant B 19a provided in the central part of the most windward row from the windward direction refrigerant row 18 provided in the central portion of the most windward row with respect to the airflow direction, A branch pipe 16 that branches the refrigerant flow up to 19b from one pass to two passes, and a separating means 21 that thermally separates the fin 1 in the longitudinal direction of the fin 1 at least in the windward direction. At least a part of the upper row is composed of the 1-pass section R1, and it is located near the upwind refrigerant B 18 of the two heat transfer pipes D12 and D17 connected to the 2-pass sections Rl and R2 of the branch pipe 16. By configuring the fins that are in close contact with the heat transfer tube D17 and the fins that are in close contact with the upwind refrigerant coolant 18 to be thermally separated by the separating means 21, thermal loss in the fin 1 can be reduced. An air conditioner that can improve heat exchange performance can be obtained. FIG. 14 shows a configuration example when the heat exchanger 15 is also arranged on the back side. FIG. 14 is a side configuration diagram showing the indoor unit according to this embodiment. In the figure, the rear heat exchanger is disposed on the rear side of the blower 5, and the heat exchanger 15 is configured by a front heat exchanger and a rear heat exchanger that are substantially divided into three. The heat exchanger 15 is provided on the suction port 8 side of the blower 5 so as to surround the blower 5. FIG. 15 is an explanatory view schematically showing the connection state of the heat transfer tubes when a rear heat exchanger is provided. Here, for example, the case where the heat exchanger 15 is operated as a condenser is shown. As the blower 5 rotates, the air flowing from the suction port 8 flows between the heat exchange fins 1 in the same manner as in FIG. 10, exchanges heat with the refrigerant flowing through the heat transfer tubes 2, and flows out from the blower outlet 6. On the other hand, in the refrigerant flow, the refrigerant inlet is the fourth heat transfer tube D24 in the leeward row and the fifth heat transfer tube D25 in the leeward row, and the refrigerant outlet is the sixth heat transfer tube D16 in the windward row.

FIG. 16 is an explanatory diagram showing the configuration of the refrigerant path. For example, in this configuration, the refrigerant inlet is connected to the two-pass section R21, R22, R21 is for 14 heat transfer tubes, and R22 is for 14 pipes. It flows through the 1-pass section R1 and connects to the refrigerant outlet. The black circles in the two-pass sections R21 and R22 indicate the part connected from the leeward heat transfer tube to the upwind heat transfer tube.

[0060] As shown in FIG. 15, the upper refrigerant flow path passes through the heat transfer tubes D24 and the two-pass portions D24 to D21, which are the leeward row refrigerant ports provided in the center of the lee row of the front heat exchanger. , Downward heat transfer tubes D216 to D213 of the rear heat exchanger, flow into the upwind row when flowing from the heat transfer tube D213 to the heat transfer tube D113, heat transfer tubes 0113 to 0116, upwind heat transfer tubes Dl l, D12 of the front heat exchanger And flows from the short connection pipes 16a and 16b of the three-way bend 16 through the heat transfer pipes D13 to D16 to the refrigerant outlet which is the windward upstream refrigerant outlet. That is, as shown in FIG. 16, from the refrigerant inlet to the refrigerant outlet, the two-pass portion R21 and the one-pass portion R1 pass through the heat transfer tube 2 of 18 lengths.

[0061] On the other hand, the lower-side refrigerant flow path is upwinded by the heat transfer tube D25, which is the most leeward row cooling medium provided in the center of the leeward row of the front heat exchanger, the two-pass portions D25 to D212, and the heat transfer tube D212. Inflow into the line, wind through heat transfer tubes D112 to D17, long connection pipe 16c of 3-way bend 16, heat transfer pipe D17 of front heat exchanger, connection pipe 16b, 1 path section D13 to D16 of front heat exchanger It flows to the refrigerant outlet, which is the windward uppermost refrigerant port provided in the center of the upper row. That is, as shown in Fig. The loca also passes through the 2-pass section R22 and 1-pass section Rl to the refrigerant outlet, and flows through the heat transfer tube 2 that is 18 in length.

[0062] Even in this configuration, the refrigerant flow path is configured by the two-pass portions R21 and R22 at the portion where the gas ratio near the refrigerant inlet is large, thereby reducing the pressure loss and reducing the burden on the compressor 10. The heat-cooling performance is improved by configuring the supercooling part near the outlet of the cooling medium with a one-pass part R1.

[0063] The refrigerant temperature change and the air temperature change by the heat exchanger 15 configured as shown in FIGS. 14 to 16 are the same as those in FIG.

As is clear from FIG. 16, there are only one location where all of the plurality of refrigerant flow paths flow from the second leeward row indicated by black circles to the first leeward row. That is, in the refrigerant flow path of the upper refrigerant flow path and the lower refrigerant flow path, the flow of the refrigerant flows in one direction sequentially from the leeward row to the windward row. As a result, as shown in FIG. 13, the temperature change on the refrigerant side is monotonously decreased from the refrigerant inlet to the refrigerant outlet, almost parallel to the temperature change on the air side, and the temperature difference between the air temperature and the refrigerant temperature. Are always kept even. For this reason, heat exchange between the refrigerant and the air is efficiently performed, so that the heat exchanger capacity can be improved.

[0064] As described above, even when the rear heat exchanger is provided, the heat exchange capacity can be improved by configuring each of the plurality of refrigerant channels to flow in order from the leeward row to the windward row. Even in this case, a branch pipe 16 connected to the heat transfer pipe 2 and partially increasing or decreasing the number of paths of the refrigerant flow path by the heat transfer pipe 2 is provided, and at least between the refrigerant inlets 19a and 19b and the refrigerant outlet 18 is provided. The cooling medium flowing through each of the plurality of refrigerant flow paths formed so as to partially pass through different paths The leeward row force in the direction of the airflow Heat exchange performance is improved by exchanging heat efficiently in any part of the heat exchange ^^, and an air conditioner with high energy efficiency can be obtained.

[0065] In the configuration shown in FIG. 14, the thermally separated portion of the fin 1 is separated by the rear heat exchange ^^ and the front heat exchange ^^, that is, between the heat transfer tubes D116 and D11. It is between the heat transfer tubes D216 and D21, and the part where the notch is provided on the windward side of the fin 1 of the front heat exchanger, that is, between the heat transfer tubes D15 and D16, and between the heat transfer tubes D19 and D110. Here, the viewpoint power of effectively using the space in the housing is cut into three front heat exchanges, and the front heat exchanger is arranged in an arc along the outer periphery of the blower 5. This results in a thermal separation hand As a step, the heat transfer tube D15 and the heat transfer tube D16 are thermally separated by cutting the fin 1 in the windward direction about half the width of the fin in the airflow direction. In addition, heat is cut between the refrigerant outlet 18 and the supercooling section where the temperature is high, that is, between the fin 1 that is in close contact with the heat transfer tube D16 and the fin 1 that is in close contact with the heat transfer tube D17. Interchange performance can be improved. The refrigerant is becoming supercooled.By thermally separating the start part of the 1-pass part R1 and the refrigerant outlet 18, the heat transfer tubes through which the refrigerant with a large temperature difference flows are thermally separated to reduce heat loss. The heat exchange performance can be improved.

FIG. 17 shows the rate of increase of the heat exchanger capacity according to this embodiment with respect to the conventional heat exchanger capacity, and the vertical axis is%. In the heat exchanger without a back surface, it shows (heat exchange capacity during heating in fully counterflow shown in Fig. 10) / (heat exchanger capacity in heating with non-perfect countercurrent flow as shown in Fig. 10). Fig. 14 shows (heat exchange capacity during heating in fully counterflow shown in Fig. 14) / (heat exchanger capacity during heating in non-perfect counterflow in the past). The configuration of the conventional non-perfect counter flow is that the fin shape, heat transfer tube pitch, heat transfer tube diameter, number of heat transfer tube stages, fin pitch, and number of passes are compared for both the heat exchanger without back and the heat exchanger with back. The flow of the path is changed with the same configuration as the flow of the refrigerant. The refrigerant force that flows through each of the refrigerant flow paths between the refrigerant inlet and the refrigerant outlet flows from the leeward row to the windward row in the airflow direction, and further upwind It was assumed that it flowed from the row to the leeward row and again from the leeward row to the leeward row.

[0067] As shown in Fig. 17, a capacity increase of about 8-9% was obtained with the heat exchanger without a back surface, and a capacity increase of about 7% was obtained with heat exchange with the back surface. In other words, when heat exchange is used as a condenser, the refrigerant flowing in each of the refrigerant flow paths between the refrigerant inlet and the refrigerant outlet flows in one direction sequentially between the rows to the leeward force in the airflow direction. As a result, it was possible to increase the heat exchange capacity of both the heat exchanger without a back surface and the heat exchanger with a back surface.

Figure 17 shows that the heat exchanger without the back has a greater increase in heat exchange capacity than the heat exchanger with the back. This is because in the configuration of the indoor unit shown in Fig. 10, there is no back heat exchanger because the air flow in one path of heat exchanger 15 is larger in the heat exchanger without back than in the heat exchanger with back. This is because sufficient cooling can be obtained in the case. However, this changes in the air flow path in the indoor unit, that is, the arrangement and suction of each member of the indoor unit. It changes depending on the arrangement of the inlet and outlet.

FIG. 18 is a graph showing heat exchanger capacity Z weight W Z (K X kg) in a heat exchanger without a back surface and a heat exchanger with a back surface. Here, the weight is the weight of the fins and heat transfer tubes that constitute the heat exchanger, and indicates the heat exchange capacity with respect to the weight when the weight is changed by increasing the number of stages of the heat transfer tubes.

Comparing the heat exchanger capacity Z weight in Fig. 18, it can be seen that the heat exchanger without a back surface can obtain a larger capacity than the heat exchange with a back surface. In the case of the configuration shown in FIG. 10, since the wind speed on the back side of the blower 5 is slow, the heat exchange capacity of the back heat exchanger can be increased so much as it can be obtained by the heat exchange on the front side. Absent. Therefore, when trying to change the size of the heat exchanger 15 in the configuration shown in FIG. 10 or FIG. 14, for example, increase the number of fins, the number or rows of heat transfer tubes, the size of the fins, etc. When the heat exchanger is installed, the heat exchange provided on the front side of the blower 5 is larger than the heat exchanger provided on the back side of the blower 5 or the heat exchanger provided on the back side. Improve the ability to translate. However, this also changes in the air flow path in the indoor unit, similar to the rate of increase in heat exchange capacity shown in FIG. 17, that is, depending on the arrangement of each member of the indoor unit, the arrangement of the inlet and outlet, etc. Change.

[0069] In Fig. 14 to Fig. 16, the configuration example in which the heat exchanger is provided on the back side and the heat exchanger is operated as a condenser has been described, but even when the heat exchange is operated as an evaporator, It is the same. That is, as in the configuration of FIG. 14, the rear heat exchanger is configured to surround the blower 5 along with the front heat exchanger, and the branching portion that partially increases or decreases the number of refrigerant flow paths by the heat transfer tubes. The refrigerant flowing through each of the plurality of refrigerant flow paths passing through different paths at least partly between the refrigerant inlet and the refrigerant outlet is in the direction of the windward force in the direction of the airflow in the leeward row and in one direction between the rows. By configuring the refrigerant flow path to flow, the air temperature change and refrigerant temperature change can be made almost evenly parallel even when operated as an evaporator, and the heat exchange capacity can be improved.

[0070] The airflow shown in Figs. 6 and 10 is a measurement result in each configuration or a calculation result obtained by simulation. If the front panel 7 is also configured to allow air to flow, the airway configuration and airflow will change. Due to the positional relationship with the machine 5, the upwind row of the heat exchanger is on the inlet side, and the downwind row is on the blower side. Therefore, each of the plurality of refrigerant flow paths flows in one direction sequentially from the windward row to the leeward row when operating as an evaporator, or sequentially from the leeward row to the windward row when operating as a condenser. By configuring to flow in one direction, the refrigerant temperature change and the air temperature change can be made almost parallel, and the heat exchange performance can be improved.

In order to improve the heat exchange performance by using the part with high wind speed, it is only necessary to perform actual measurement in the simulation and place the 1-pass part in the part with high wind speed obtained as a result.

[0071] When heat exchange is used as a condenser, in the above, the force described for the configuration in which the number of passes is reduced to two passes and one pass is not limited to this. It is possible to reduce the number of paths from 3 or more to 1 path. It can also be applied to the case where the number of paths is 3 or more and the number of paths is reduced to 2 or more.

[0072] In the above description, the configuration has two rows of the windward heat transfer tube and the leeward heat transfer tube in the airflow direction, but may have a configuration having three or more heat transfer tube rows. In this case, for example, in the case of three rows, the refrigerant flowing through each of the plurality of refrigerant flow paths between the refrigerant inlet and the refrigerant outlet flows in sequence between the rows from the leeward row to the windward row in the airflow direction. If it is configured to flow in order of lower row> middle row> upwind row.

[0073] FIG. 19 relates to the heat exchange ^^ according to this embodiment, and is a flowchart showing a process of attaching the heat exchange ^^ to the indoor unit. FIG. 20 is a diagram showing the heat exchanger according to this embodiment being assembled. It is explanatory drawing which shows the state before installing in a unit frame.

The conventional heat exchanger mounting process for indoor units involves the step of inserting the hairpin 3 into the laminated fins and then expanding the tube to tightly bond the fin and the hairpin 3 when forming the finned tube heat exchanger. To do. Next, after brazing the U-bend 4 and installing it in the housing, the 3-way bend 16 was brazed to complete the heat exchange.

When manufactured in a conventional process, when brazing the three-way bend 16 after installation in the housing, the position 1 of the fins constituting the heat exchanger 15 moves slightly, and the heat exchange 5 is accurately performed. It was hard enough to fit in the case.

In this embodiment, as shown in FIG. 19, the fin and the heat transfer tube are fixed by expansion (S Tl), U-bend 4 is connected to heat transfer tube 2 by brazing, for example, and a heat transfer tube end connection step is performed in which two end portions of heat transfer tube 2 are connected (ST2). Next, a branch pipe connection process for connecting the three-way bend 16 to the heat transfer pipe 2 by, for example, brazing is performed (ST3), and then installed in the housing (ST4). The heat exchange in the housing is fixed in the housing by, for example, fitting a hook provided on the case and a hook provided on the heat exchange side.

In this manufacturing method, the three-way bend 16 is connected to the heat transfer tube 2 before mounting the heat exchanger in the casing, so that the connection work of the three-way bend 16 can be connected to the heat transfer tube 2 without fail. Furthermore, since the heat exchanger 15 is close to the completed state, the work process after the heat exchanger 15 is installed in the housing can be reduced, and the position of the heat exchanger 15 can be prevented from being shifted after being installed in the housing. .

[0075] Thus, the refrigerant between the refrigerant inlet and the refrigerant outlet is inserted substantially perpendicular to the plurality of fins 1 arranged in parallel at a predetermined interval, arranged in the longitudinal direction of the fins 1 and connected in a plurality of rows in the airflow direction. Inserted into fin 1 when manufacturing heat exchanger tube 2 that constitutes the flow path and branch pipe 16 that is connected to the connection section of the heat transfer pipe and partially increases or decreases the number of paths of the refrigerant flow path Two ends of the fixed heat transfer tube 2 are connected by U-bend 4, which is a connection pipe, and the heat transfer tube end connection process (ST2) and the connection pipes 16a, 16b, and 16c of the branch pipe 16 are transmitted. After the branch pipe connection process (ST3) for connecting to the end of the heat pipe 2, and the heat transfer pipe end connection process (ST2) and the branch pipe connection process (ST3), a process of fixing the heat exchanger 15 in the housing is performed. Thus, it is possible to obtain a method of manufacturing an air conditioner in which heat exchange can be easily and accurately installed in the housing.

In the process of FIG. 19, the order of the heat transfer tube end connecting step (ST2) and the branch tube connecting step (ST3) may be reversed. U-bend 4 and 3-way bend 16 should be connected to heat transfer tube 2 before installing heat exchanger in the housing.

[0077] In addition, in the heat exchanger in Embodiment 1 and the air conditioner using the heat exchanger, as the refrigerant, for example, an HCFC refrigerant, an HFC refrigerant, an HC refrigerant, a natural refrigerant, or a refrigerant of these refrigerants. The effect can be achieved with any type of refrigerant, such as several types of refrigerants. HCFC refrigerant, for example, R22, HFC refrigerant, for example, R116, R1 25, R134a, R14, R143a, R152a, R227ea, R23, R236ea, R236fa, R245c a, R245fa, R32, R41, RC318, etc. and some mixed refrigerants such as R407A, R407B, R407C, R407D, R407E, R410A, R410B, R404A, R507A, R508A, R508B, etc. Examples of HC refrigerants include butane, isobutane, ethane, propane, and propylene, and several mixed refrigerants of these refrigerants. Examples of natural refrigerants include air, carbon dioxide, and ammonia, and some of these refrigerants. There are mixed refrigerants.

[0078] Further, the same effects can be obtained by using the force shown in the example of air and refrigerant as the working fluid, and using other gas, liquid, gas-liquid mixed fluid.

[0079] Further, the materials of the heat transfer tubes and the fins are not particularly limited, and different materials may be used. By using the same material such as copper for the heat transfer tubes and fins and aluminum for the heat transfer tubes and fins, it is possible to braze the fins and the heat transfer tubes, and the contact heat transfer coefficient between the fins and the heat transfer tubes is dramatically increased. And heat exchange capacity is greatly improved. Recyclability can also be improved.

[0080] Normally, a hydrophilic material is applied to the fin before the heat transfer tube and the fin are brought into close contact. However, when the heat transfer tube and the fin are brought into close contact by brazing in the furnace, the heat transfer tube and the fin are brought into close contact with each other. It is desirable to apply a hydrophilic material to the fin later. By applying a hydrophilic material to the fins after brazing in the furnace, the burning of the hydrophilic material during brazing can be prevented.

[0081] In addition, heat transfer performance can be improved by applying a heat radiation coating that promotes heat transfer by radiation on the plate-like fins. Also, by applying a photocatalyst, the hydrophilicity on the fins can be improved, and when the heat exchanger is used as an evaporator, dripping of condensed water into the blower can be prevented.

[0082] The heat exchanger described in the first embodiment and the air conditioner using the heat exchanger include mineral oil, alkylbenzene oil, ester oil, ether oil, fluorine oil, and the like. The effect can be achieved with any refrigeration oil, whether or not the refrigerant and oil melt.

[0083] Here, the power outdoor unit described for the indoor unit of the air conditioner also includes a heat exchanger and a blower for exchanging heat between the outside air and the refrigerant. The configuration for operating the heat exchanger as an evaporator or a condenser is the same as described above. Therefore, the features in this embodiment can be applied to the outdoor unit. [0084] As described above, the air conditioner according to the present invention has the following effects.

[0085] In an air conditioner including a casing provided with an inlet and an outlet and a cross-flow fan accommodated in the casing, a front non-permeable panel is used on the front side, and an upper suction grille is used. A heat exchanger with a plurality of fins arranged in the middle of the wind circuit from the cross-flow fan to the cross-flow fan or in the middle of the wind circuit from the cross-flow fan to the outlet, each heat exchanger being parallel at a predetermined interval And a large number of fins through which gas flows, and a large number of heat transfer tubes inserted into the fins at a substantially right angle and through which the fluid flows, and are arranged substantially on the front side from the center of the blower in the housing. When the heat exchanger tube center line is formed with an obtuse angle, it consists of two upper and lower heat exchangers (relative to the direction of gravity), and when these two heat exchangers are used as condensers Is the air upstream direction from the refrigerant inlet to outlet Alternatively, the refrigerant flow path is configured so that the refrigerant flows in a direction perpendicular to the air flow, a part of the refrigerant flow path is defined as one pass, the other refrigerant flow path is defined as two passes, and the one-pass portion and the In the three-way bend that connects the two-pass sections, the two connection ports are connected so as to straddle the upper and lower heat exchangers, so an air conditioner with high heat exchange capability can be obtained.

[0086] Since the refrigerant outlet when used as the condenser and the connecting portion of any of the three-way pipes are arranged adjacent to each other and arranged in different heat exchangers, an air conditioner having a large heat exchange capability is obtained. be able to.

[0087] The 1-pass part is arranged at the uppermost stream in the upper air flow direction and at the lowermost part of the heat exchanger, and when used as a condenser, the refrigerant outlet is the lowermost part in the gravity direction of the upper heat exchanger ^^ The length of the 3-way bend bifurcation and the lower connection in the gravity direction is longer than the length of the 3-way bend bifurcation and the upper connection in the direction of gravity, so an air conditioner with high heat exchange capability can be obtained. .

[0088] Since the fin shapes, heat transfer tube pitch, heat transfer tube diameter, heat transfer tube stage number, and fin pitch of the two heat exchangers are the same, an air conditioner having a large heat exchange capability can be obtained.

[0089] After the upper heat exchanger and the lower heat exchanger are connected by the three-way pipe, they are fixed to the indoor unit, and the U-bend is connected, so that an air conditioner with easy assembly can be obtained. It is out. Explanation of symbols

1 fin

2 Heat transfer tube

3 Hairpin

4 U—Bend

5 Blower

6 Air outlet

7 Front panel

8 Suction port

9 Blower motor

10 Compressor

11 Indoor heat exchanger 12 Outdoor heat exchanger 13 Expansion valve

14 Channel switching valve

15 Heat exchanger

16 branch pipe

18 Upstream refrigerant B 19a, 19b Downstream refrigerant B 20 Branch

21 Separation means

Claims

The scope of the claims

[1] A blower that guides the gas flowing in from the suction port to the blowout port, a heat exchanger that is provided on the suction port side of the blower and that exchanges heat between the gas and the refrigerant, and that is provided in the heat exchanger, Refrigerant between the refrigerant inlet and the refrigerant outlet inserted into a plurality of fins arranged in parallel at a predetermined interval in the rotation axis direction of the blower at a substantially right angle, forming a row in the longitudinal direction of the fins and connected in a plurality of rows in the airflow direction A heat transfer pipe constituting the flow path, and a branch pipe connected to the connection portion of the heat transfer pipe and partially increasing or decreasing the number of paths of the refrigerant flow path by the heat transfer pipe, the refrigerant inlet and the refrigerant Refrigerant force flowing through each of the plurality of refrigerant flow paths passing through different paths at least at a part between the outlets. From the windward row in the airflow direction to the leeward row or the leeward row force. Air conditioning, characterized by being configured to flow .

[2] One of the refrigerant inlet and the refrigerant outlet is disposed on the heat transfer tube in the center of the windward row, and the other is provided in the heat transfer tube in the center of the windward row, and the windward row 2. The air conditioner according to claim 1, wherein a heat transfer tube at an end in a longitudinal direction of the air conditioner is connected to a heat transfer tube in a row adjacent to the leeward row.

[3] The branch pipe has a connection pipe connected to three or more heat transfer pipes, and among the connection pipes connected to the heat transfer pipe on the downstream side when increasing the number of paths, the transfer pipe below the gravitational direction is used. The branch pipe so that a pressure loss when the refrigerant flows through the connection pipe connected to the heat pipe is larger than a pressure loss when the refrigerant flows through the connection pipe connected to the heat transfer pipe above the gravitational direction. The air conditioner according to claim 1 or 2, wherein the air conditioner is configured.

[4] The length of the connection pipe connected to the heat transfer pipe below the gravity direction of the branch pipe is longer than the length of the branch pipe to the connection pipe connected to the heat transfer pipe above the gravity direction. The air conditioner according to claim 3, wherein:

[5] It is assumed that the number of passes is increased or decreased in the one-pass portion and the plurality of pass portions, and the heat transfer tubes constituting the one-pass portion are arranged in the most upwind line in the airflow direction. The air conditioner according to any one of claims 1 to 4, wherein the air conditioner is characterized.

[6] When operating the heat exchange as a condenser, the refrigerant flow path has multiple passes. A fin that is in close contact with the heat transfer tube at the refrigerant outlet, and a fin that is in close contact with the heat transfer tube that is located closest to the refrigerant outlet among the heat transfer tubes that are respectively located on the most downstream side of the plurality of pass portions. The air conditioner according to any one of claims 1 to 5, wherein the air conditioner is thermally separated.

[7] A blower that guides the gas flowing in from the suction port to the blowout port, a heat exchanger that is provided on the suction port side of the blower and exchanges heat between the gas and the refrigerant, and is provided in the heat exchanger, A refrigerant inlet and a refrigerant outlet are inserted into a plurality of fins arranged in parallel at a predetermined interval in the rotation axis direction of the blower at a substantially right angle, and are arranged in a row in the longitudinal direction of the fins and connected in a plurality of rows in the gas flow direction. The air flow direction from the heat transfer tubes constituting the refrigerant flow path between them and the upwind row refrigerant port provided in the heat transfer tube in the center of the most upwind row with respect to the airflow direction provided in the connection portion of the heat transfer tubes In contrast, a branch pipe that branches the refrigerant flow from the 1st path to the 2nd path to the leeward stream refrigerant port provided in the heat transfer pipe in the central part of the most downwind line, and at least an upstream portion of the airflow of the fin Separating means for thermally separating vertically in the longitudinal direction. The heat transfer tube described above, wherein at least a part of the heat transfer tubes in the upper row is configured by the one pass, and the heat transfer tube located near the upwind row refrigerant port of the two heat transfer tubes connected to the two pass portions of the branch pipe. The air conditioner is configured such that the fins that are in close contact with the fins and the fins that are in close contact with the upwind refrigerant ports are thermally separated by the separation means.

[8] The heat exchanger disposed on the front side of the blower is configured by arranging two heat exchangers having substantially the same fin shape in a "<" shape. The air conditioner according to any one of claims 1 to 7.

[9] The heat exchanger is composed of an upper heat exchanger and a lower heat exchanger separated vertically, and the refrigerant outlet when the heat exchanger is operated as a condenser is connected to the gravity of the upper heat exchanger. It is provided in the heat transfer pipe located at the lowest direction in the direction and at least one of the connection pipes connected to the upstream side of the refrigerant flow among the connection pipes of the branch pipes is arranged in the lower heat exchange The air conditioner according to any one of claims 1 to 8, wherein the air conditioner is characterized.

[10] A plurality of fins arranged side by side at a predetermined interval are inserted substantially perpendicularly to form a refrigerant flow path between the refrigerant inlet and the refrigerant outlet by forming a row in the longitudinal direction of the fin and connecting in a plurality of rows in the airflow direction. And a heat exchanger having a branch pipe connected to the connection portion of the heat transfer pipe and partially increasing or decreasing the number of paths of the refrigerant flow path is inserted and fixed to the fin. A heat transfer tube end connection step in which two of the end portions of the heat transfer tube are connected by a connection pipe, a branch pipe connection step of connecting the connection pipe of the branch pipe to an end of the heat transfer tube, and the heat transfer tube A method of manufacturing an air conditioner, comprising: a step of fixing the heat exchanger in a housing after the end connecting step and the branch pipe connecting step.